Flap control and drive systems for aircraft are well known in the art. On certain aircraft, for example, the flaps may be controlled such as by activating a lever or switch which energizes a drive motor to drive the flaps to the selected position. In such systems, the pilot may visually check the condition of the flaps and if the selected position is intermediate between a full-up or a full-down flap position, the pilot may deactivate the lever or switch at the proper intermediate position.
The present flap control circuitry permits the pilot to select the position of the flaps by moving the lever to a point corresponding to the desired position of the flaps. The flap control circuitry will energize a motor, which is mechanically connected through flexible drive couplings, to drive the flaps to the desired position and then cause the motor to be deenergized, as depicted in the sketch of FIG. 2. The pilot can rely on the control circuitry to drive the flaps to the proper position, and once the pilot has selected the proper flap position, he can devote his attention to flying the aircraft.
Importantly, the inventive system includes circuitry to monitor the instantaneous position or angle of the flaps mounted on each of the wings and to compare the angles or positions of the flaps to each other. If the positions or angles of the flaps are more than a preselected tolerance apart, the system provides an indication that the movement and position of the flaps are, in fact, not synchronized and shuts down.
Further, the control circuitry of the invention includes various associated logic circuits for indicating faults or failures in the control circuitry itself.
The foregoing features and advantages of the present invention will be apparent from the following more particular description of the invention. The accompanying drawings listed hereinbelow are useful in explaining the invention wherein: